The year and a half between the release of Parsley, Sage, Rosemary and Thyme, and March 1968, when Bookends saw the light of day, had seen the Beatles complete their transformation from pop stars to prophets with Sgt. Pepper's, while, on the West Coast, the Summer of Love and the Monterey Pop Festival signaled an opening up of young society to new sounds and the altered state of consciousness that many then believed was the prerequisite for experiencing them. Inevitably, the duo was seduced by this dramatic profusion of aural and thematic possibilities, but, rather than jumping on the acid-rock bandwagon, as so many of their contemporaries were doing, Simon & Garfunkel used the colors of the newly expanded musical palate as carefully as they'd used their voices and acoustic guitar – to serve the sense and spirit of their songs.

And what songs they were, dense with meaning and implication. The most literary of albums, the aptly titled Bookends was the musical equivalent of a book containing a novella – in the form of a conceptual song cycle – and a series of interrelated short stories, among them, The Graduate's linchpin song, "Mrs. Robinson," as well as "A Hazy Shade of Winter," "Fakin' It," the Orwellian "At the Zoo," and the wistful "Punky's Dilemma," a reflection on the lost innocence of our childhoods. Overtly ambitious, the record functioned as a meditation on the passage of life and the psychological impact of life's irreversible, ever-accumulating losses. The song cycle described the life and death of the American Dream, the romantic notion we'd grown up embracing, expressed most poignantly in the vivid narrative "America," a rueful anthem of hope and hopelessness.

But Simon & Garfunkel didn't stop there, expanding the scope to the universal – the relentless march toward old age and death. The elegiac "Old Friends" was underpinned by a lovely string and horn arrangement that threatened to erupt into cacophony, a la the Beatles' "A Day in the Life," before the storm passed and the focus shifted back to the image of two old men sitting on a park bench, "silently sharing the same fear." The song flowed seamlessly into the "Bookends Theme," which Simon brought to a close with the suggestion, "Preserve your memories; they're all that's left you."